Traditionally plates for printing presses were produced by hand or were set with movable type. Improvements have led to the use of automatic machines such as linotypes. A particularly effective commercial machine for automatically applying the liquid photopolymerizable resin is marketed by Hercules, Inc. under the designation SRA. In one form of the SRA machine a trough is provided in the form of an elongated tilt bucket which pours the resin material onto a moving sheet after the bucket is tilted. A disadvantage with this form of machine, however, is that it incorporates only a single trough and thus can provide only a single layer of resin. It is desirable in many applications to provide plural layers of resin to the plate. This process is known as "capping". A variation of the SRA machine includes a mainfold in addition to the trough for applying a second layer of resin. The manifold is electrically operated to apply its resin at the desired time. This leads to an increased complexity and cost for such variation.
Reference is made to U.S. Pat. Nos. 4,266,007, 4,332,873 and 4,383,759 which relate to the production of a capped printing plates. Reference is also made to U.S. Pat. No. 4,056,423 relating to platemaking. It would be desirable if a plate making machine were provided combining the advantages of the capping process in a fully automated machine such as the SRA machine.